#include <iostream>
using namespace std;

bool panduanzhishu_(int a)
{
    for(int i =2; i<a; i++)
    {
        if (a%i==0)
        {
            return false;
            break;
        }
    }
}


int main()
{
    int num1;
    cout<<"please enter an integer: "<<endl;
    cin>>num1;
    bool result=panduanzhishu_(num1);            
    if (result)
    {
        cout<<"this is a zhishu ."<<endl;
    }
    else{
        cout<<"this is not a zhishu ."<<endl;
    }

    return 0 ;
}